Expansion coupler



FIG. 1 is a front perspective view of an expansion coupler of my newdesign shown in environmental use.

FIG. 2 is a rear perspective view thereof.

FIG. 3 is a right side view thereof, the left side view being a mirrorimage thereof.

FIG. 4 is a front view thereof.

FIG. 5 is a rear view thereof.

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

The broken lines shown represent environmental subject matter and formno part of the claimed design.

CLAIM The ornamental design for an expansion coupler, as shown anddescribed.